What with the early openings, manic crowds and potential for violence, it's no wonder that many Black Friday shoppers choose to forgo malls and browse on the Web instead.

Internet retailers are catching on fast. That's why 97% of merchants selling online plan to offer special promotions during the Thanksgiving weekend, a jump from 90% last year, according to a holiday survey from Shop.org.

Retailers are poised to compete ferociously during the crucial holiday season, when they can rake in up to 40% of their annual sales.

Almost half will roll out discounts on Thanksgiving Day. A record 85% have promotions planned for Cyber Monday, the Monday after Thanksgiving when retailers try to lure shoppers who just returned to work.

"Consumers are increasingly shopping and buying both online and in-store this holiday season,” said Shop.org Executive Director Vicki Cantrell. “Savvy retailers are getting the word out to customers about in-store offers and events using online vehicles such as Facebook, email, Twitter and mobile alerts."